1256823461 has 2 divisors, whose sum is σ = 1256823462. Its totient is φ = 1256823460.

The previous prime is 1256823439. The next prime is 1256823473. The reversal of 1256823461 is 1643286521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 831226561 + 425596900 = 28831^2 + 20630^2 .

It is a cyclic number.

It is not a de Polignac number, because 1256823461 - 2³⁰ = 183081637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1256843461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628411730 + 628411731.

It is an arithmetic number, because the mean of its divisors is an integer number (628411731).

Almost surely, 2^1256823461 is an apocalyptic number.

It is an amenable number.

1256823461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256823461 is an equidigital number, since it uses as much as digits as its factorization.

1256823461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69120, while the sum is 38.

The square root of 1256823461 is about 35451.7060379328. The cubic root of 1256823461 is about 1079.1738827051.

The spelling of 1256823461 in words is "one billion, two hundred fifty-six million, eight hundred twenty-three thousand, four hundred sixty-one".